Testing

Tips on how to unit test with the kernel. Interactive tests are not covered.

Official testing methods

None. Not even unit tests.

Third party projects:

A kernel module can be inserted and removed while the kernel is running, so it may prevent a time costly rebooting.

However, if you make an error at startup (dereference null pointer for example), the kernel module may become impossible to reinsert without a reboot. http://unix.stackexchange.com/questions/78858/cannot-remove-or-reinsert-kernel-module-after-error-while-inserting-it-without-r/

Furthermore, if your module messes up bad enough, it could destroy disk data, so be careful.

Consider using a virtual machine instead.

The best way to tests a fully blown kernel modification in full security.

Get your hands on Oracle VirtualBox and shoot away.

You can then easily test your kernel modules on the virtual machine by using a script like the following from the virtual machine:

UNAME=
DIRNAME=kernel

sudo rm -rf $DIRNAME
sudo cp -r /media/sf_kernel $DIRNAME
sudo chown -R $UNAME $DIRNAME
cd $DIRNAME
make clean
make run

Where:

UNAME:

Username of the user on the virtual machine.
DIRNAME:

Directory name to be used for compilation relative to current dir.

Its content is removed at every compile, so don't put important stuff in there.
/media/sf_kernel:

Directory shared between client and host, that corresponds to the host's location of the module code and Makefile.